The invention relates to a combination of a ski binding, particularly a cross-country, touring or telemark binding and of a boot adapted thereto, the forward end of which is held in the binding by a resiliently biased clamping element in such a way that the heel of the shoe can be freely raised when used in touring, cross-country skiing or the like use.
Such combinations of a ski binding and of a boot adapted thereto are generally known; in the known solutions a clamp cable is passed around the boot heel as a retaining member. Such a construction is for example described in FR-A 756 374 or CH-A-194 783. For a corresponding construction of a touring ski binding, reference is made to DE-C 35 39 315. All these known combinations are relatively bulky in construction. A disadvantage is also that lifting of the boot heel during touring, cross-country skiing or downhill skiing in the telemark style is in fact prevented by the clamp cable passed around the boot heel. In addition, when the clamp cable is arranged around the boot heel the said heel can be moved laterally, so that exact lateral guidance of the ski is not possible. The transfer of power to the ski is likewise impaired. Finally, a considerable disadvantage is that the position of the bending lIne of the sole extending transversely to the longitudinal direction of the boot or sole is not defined. It migrates within a relatively large area, i.e. is displaced upon each lift of the boot heel. Consequently, the solE and boot deformation forces alter in a corresponding way. The cross-country skier is subjected to varying degrees of stress upon each lift of the boot heel.
There is known from DE-OS 41 03 068 a ski cross-country binding in which a clamp cable which can be passed around the boot heel fixes the ski boot to the cover surface of a ski-mounted toe iron by means of a clamp cable coupled to a tightening mechanism. In this case the clamp cable has a device for altering its effective length, and a part of the clamp cable is replaced by a traction spring. At the portion of the clamp cable which can be passed around the boot heel, a clamp lever which can be supported on the boot sole is mounted to pivot about a pivotal axis located parallel to the clamp cable. In this binding also, the above mentioned problems arise, due to the varying sole and boot deformation forces.
There is known from DE-GM 16 96 548 a ski binding with a tightening strap engaging on the forward end of a ski boot, the tightener mounted in front of the ski boot on the ski cover surface being engaged in a metal tab secured to the forward sole of the ski boot and drawing it between retaining jaws. This engagement binding is intended to ensure that it releases automatically during disconnections, as soon as the rear portion of the ski boot is raised to an unusual height from the ski cover surface. Such a ski binding enables only imprecise guidance of the ski and power transmission to the ski and is unsuitable both for cross-country skiing or for downhill skiing in the telemark style.